• Survey Research
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• v.11 no.3
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• pp.103-114
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• 2010

It is difficult to obtain the population information of target variables when a new sampling design for successive survey is executed. In a research of the Korea National Tourism Survey, we propose a method for selection of efficient stratification variables which are found in a combination of a existing sample data and a new frame list. At first, if there isn't common identification number between the frame list and the sample data, we find a device to substitute for absence of identification number. At second, we suggest a method to search stratification variables correlated with target variables using statistical methods like regression analysis.

• The Korean Journal of Zoology
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• v.3 no.2
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• pp.13-18
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• 1960

For the study on the sex ratio in natural populations of the different localities, the amphibian species were collected as the materials at the seven localities in Korea, and were obtained the following results. The sex ratios of each amphibian species suggest that each has it's own specific sex rations the following list. Rana nigromaculata H. : 109-39, Rana rugosa SCH. : 67.44, Rana temporaria coreana O. : 158.45, Hyla arborea japonica G. : 137.70. In Rana nigromaculata H. the average sex ratio was 109.39 as the above list, and its was reached statistically significant level according to the different localiies. The sex ratio was generally higher in the eastern area than that in the western area in this country. The sex ratio of the adult frogs of Rana nigromaculata H. was 135.18 , and it has a statistically significant level by each locality but the sex ratio of the younger frogs of the same species was 100.97 which was a little lower than that in the adult, and it was not laid at a significant level according to the localities. There is no doubt that the difference of sex ratios according to the localities was mainly due to the different ratios of the adult frogs which were effected on the constitution of sex by environmental factors in each locality.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.2
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• pp.150-159
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• 2009

The heterogeneous fleet vehicle routing problem(HVRP) is a variant of the classical vehicle routing problem in which customers are served by a heterogeneous fleet of vehicles with various capacities, fixed costs and variable costs. We propose a new conceptual HVRPCR(HVRP with customer restriction) model including additional customer restrictions in HVRP. In this paper, we develop hybrid particle swarm optimization(HPSO) algorithm with 2-opt and node exchange technique for HVRP. The solution representation is a n-dimensional particle for HVRP with N customers. The decoding method for this representation starts with the transformation of particle into a priority list of customer to enter route and limit of vehicle to serve each customer. The vehicle routes are then constructed based on the customer priority list and limit of vehicle to serve. The proposed algorithm is tested using 8 benchmark problems and it consistently produces high-quality solutions, including new best solutions. The numerical results show that the proposed algorithm is robust and efficient.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5305-5321
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• 2016

In wireless communication, the multiple-input multiple-output (MIMO) system is a well-known approach to improve the reliability as well as the data rate. In MIMO systems, channel state information (CSI) is typically required at the receiver to detect transmitted signals; however, in practical systems, the CSI is imperfect and contains errors, which affect the overall system performance. In this paper, we propose a novel maximum likelihood (ML) scheme for MIMO systems that is robust to the CSI errors. We apply an optimization method to estimate an instantaneous covariance matrix of the CSI errors in order to improve the detection performance. Furthermore, we propose the employment of the list sphere decoding (LSD) scheme to reduce the computational complexity, which is capable of efficiently finding a reduced set of the candidate symbol vectors for the computation of the covariance matrix of the CSI errors. An iterative detection scheme is also proposed to further improve the detection performance.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.13-20
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• 2005

Thirty-four species of the subfamily Plusiinae were recognized from the lepidopteran expeditions to Mt. Changbai during 2000-2004. Among them, six species (Abrostola ussuriensis Dufay, Polychrysia aurata (Staudinger), P. splendida (Butler), Lamprotes mikadina (Butler), Autographa amurica (Staudinger), and A. v-minus (Oberthur)) are reported for the first time from China. Three previously reported species Antoculeora ornatissima (Walker), Autographa nigrisigna (Walker), and Syngrapha hochenwarthi (Hochenwarth) were not found in this study, Photographic images of adults of the newly known species from China and their male or female genitalia are given, with a check list of the 37 known species of the subfamily in Mt Changbai.

• The Korean Journal of Mycology
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• v.33 no.1
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• pp.38-53
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• 2005

Until recently, many scientific names of Korean Aphyllophorales have been used in a state of confusion. Korean names of Aphyllophorales species recorded until recently were listed here and, among them, 40 misnamed species were renamed according to The Proposal for the Unification of Korean Names for Mushrooms recommended by the Korean Society of Mycology in 1978. This list contains rearranged 411 species of 144 genera from 23 families in Korean Aphyllophorales.

• Journal of Korean Society for Quality Management
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• v.42 no.1
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• pp.43-61
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• 2014

Purpose: This study identifies preventive measures for VOC management by analyzing the causes and effects of factors that contribute to high risk service failure using FMEA on KORAIL VOC data. Methods: Two research methods were used. First, a Risk Priority Number (RPN) was assigned to each KORAIL VOC based on Failure Mode and Effect Analysis (FMEA). Second, multiple regression analysis was run with RPN factors that include severity, occurrence, and detection as the independent variables and customer dissatisfaction as the dependent variable. Results: Multiple regression analysis showed that RPN factors including severity, occurrence, and detection had significantly positive relationship with customer dissatisfaction. Based on these results, an FMEA was performed on VOC categories with high RPN for railroad stations including platform, ticketing, ticket verification, parking, and escalator, and VOC categories with high RPN for trains including entrance doors, cafes, air quality, announcement, and ticket verification. Conclusion: This study has practical implications to service failure management. A priority order using FMEA was established for the list of customer dissatisfactions that should be addressed to actively manage service failure, and strategies for tackling this priority list are offered.

• Korean Journal of Plant Taxonomy
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• v.47 no.3
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• pp.180-188
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• 2017

We evaluated the actual distribution, present status, and number of remnant individuals of Korean Sagittaria aginashi (Alismataceae) based on herbarium specimens and field surveys. We also reidentified Korean S. aginashi by analyzing sequences of the internal transcribed spacer (ITS) region. We found nine specimens of S. aginashi in herbaria from four localities housed at the Osaka Museum of Natural History (OSA) and at the Korea National Herbarium (KH). During our field research, we could not confirm the current statuses of two collection localities (Taereung and Ansan-si), though this was not the case for Ulsan-si. In addition, we found two new localities in Ulsan-si and Yangsan-si. These three remnant populations are distributed in wetlands in mountainous areas (elev. 480-740 m). With regard to the number of flowering and immature individuals in the three localities, there were <50 and <2,000, respectively, in total. ITS sequences demonstrated that the sequences of Korean and Japanese S. aginashi are uniform and distinct from other Sagittaria species. These results indicate that S. aginashi is a rare and threatened species in Korea. It should be listed as an endangered species on the Korean Red List and requires urgent protection by conservation programs, including the extensive surveys of other possible natural habitats.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.4
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• pp.67-89
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• 2022

This study aimed to elucidate the distribution of vascular plants on the Deok mountain in Ganghwa-gun, Korea. The results of 10 field surveys from March to October of 2019 identified 532 taxa in total, representing 482 species, 9 subspecies, 39 varieties, 1 form, and 1 hybrid in 318 genera and 105 families. The plant formation of Deok mountain is the deciduous broad-leaved and conifer mixed forest, which is the common one in the middle region of the Korean Peninsula. Among them, 301 taxa were newly recorded in this study, 7 taxa were endemic plants to Korea, 3 taxa were red list plants. The floristic target plants amounted to 41 taxa, specifically 1 taxon of grade V, 2 taxa of grade IV, 7 taxa of grade III, 9 taxa of grade II, and 22 taxa of grade I. Alien plants were recorded a total of 73 taxa with a naturalized index of 13.7%, the urbanization index was calculated to be 11.8% and 4 taxa were ecosystem disturbance plants.

• The Korean Journal of Emergency Medical Services
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• v.12 no.1
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• pp.27-41
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• 2008

Purpose : With increasing number of school accidents, it is crucial to find out necessity of first aid training among school health educator. This study has been conducted to have an clear idea on the demands and necessity for first aid training and what kind of training is most required from school health educator. Method : In this study, questionnaires from 87 school health educator in elementary, middle and high school health educator in the city D were analyzed. The survey was carned out from May 26, 2008 to June 7, 2008 and from the collected data, frequency, independent two samples t-test, paired T-test, one way ANOVA and pearson's correlation were conducted with SPSS 14.0. Result: 1. 51.61 % of nurse-teachers experienced emergency situations and the relations between the necessity they felt from experiencing those situations and demands for first aid training were not statistically meaningful(t=1.87, p= .175). 2. Necessity and demands for the first-aid training were checked with three point scale and there were statistical significance between the two with $2.44{\pm}.47$ and $2.24{\pm}.47$ respectively(t=3.275, p= .000). 3. 86.20%(75 persons) of the respondents have had received first aid training and the training they received were CPR 82.75%(72 persons), primary survey 81.60%(7l persons), contact to 911 79.30%(69 persons) and wounds treatment(lacerated wounds, bum and chilblains) 75.86%( 66 persons) in order. 4. As for the questions that ask on confidence of first-aid treatment, 80% answered they are confident on some limited kinds of treatments, 16% said they are confident and 4% answered they lack confidence. As for the treatment that they can show the highest confidence, wounds treatment topped the list with 93.24%, nose bleeding and removing foreign substance, and stanching followed the list with 82.43% and 81.08% respectively. 5. 97.67% of respondents said they were willing to take training and 89.62% answered to take the training to deal with emergency situations that are taking place in their schools. As for the question that asks for the most wanted treatments, CPR topped the list with 32.18%(28 persons) and treatment for obstruction of airway and shock followed the list with 35.63%(31 persons) and 27.59%(24 persons). Conclusion : Currently, first aid treatment has been centered on CPR, primary survey, contact to 119 and wounds treatment. However, since most of school health educator are fairly confident with wounds treatment, stanching and other first aids, in future training it will be more desirable to focus on CPR and treatment for obstruction of airway and shock that were shown to be most wanted by school health educator.